A wile back a hard drive crashed on a Laptop we bought from Best Buy and I could have replaced it, but my Dad insisted we take it to Freak Squad because it was still under warranty. They got it working (surprisingly), but now on start up and when waking from sleep mode the screen flashes a few times.
It's a Dell Inspiron 1470
You will need to wait for someone more knowledgeable that I for a solution, but I seriously doubt that the flashing is due to a defective hard drive. My guess would either be something being awry with the OS or video driver...or even the video card. However, I would discount the possibility of the video card, and focus on some kind of software issue. I don't know enough to pinpoint the problem, but if it were me, I would run diagnostics, such as chkdsk /f, sfc /scannow, reinstall the video driver, etc. Hopefully, someone will have a better solution.
Have you considered taking it back to the squad? I admit that I don't ever let anyone touch my computer besides myself, because back when I did, I usually ran into problems like you have. I would still recommend the diagnostics that I mentioned, and reinstalling the video driver. If you are comfortable inside the case, you should reseat the video card and check the connections from the card to the monitor. None of these things may help, but at least they form a foundation from which you or someone else may gain insight.
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